1. Field of the Invention
The present disclosure relates to photodetectors, and more particularly to photodetectors for ultraviolet (UV) radiation such as in flame detectors.
2. Description of Related Art
The majority of deaths associated with residential fires occur in part because of missing or ineffective smoke alarms. Of these fires, some are caused by open flame sources like lighters and/or candles. Flame sensors can provide a more rapid warning of the presence of fire or flame compared to smoke alarms, potentially reducing fire-related deaths and injuries, because they detect the radiation emitted by fire and flame instead of smoke. This radiation will generally reach a flame detector more rapidly than heat or smoke from such fire or flame tends to reach a smoke detector. These flame detectors typically include a UV sensitive film that has an absorption that renders the photodetector responsive to incident UV radiation emitted by fire or flame. The films are generally fabricated using vapor deposition routes that include chemical vapor deposition (CVD), molecular beam epitaxy (MBE), or sputtering.
Such conventional films and methods used to develop such films have generally been considered satisfactory for their intended purpose. However, there is still a need in the art for improved methods of making UV photodetectors and sensors, in particular cost. Vapor deposition routes tend to be costly in terms of up front capital, usage, energy, and maintenance, while a solution based chemical deposition route, such as spin coating, can be less expensive and can enable some of the more cost sensitive residential markets to adopt said UV photodetector technology. The present disclosure provides a solution for this need.